The Time Team is invited to a huge circular crop mark near Peterborough, referred to as a Causewayed Enclosure by archaeologists. Huge ditches mark the area, which date the site at around 6,000 years old. Some believe the ditches to be evidence of fa... (more)rming, others that they are of religious origin. Francis Pryor joins the team to get to the bottom of the mystery in just three days.